Hydraulic control valve



Jan. 12, 1943. R. K. JEFFREY ETAL 2,308,285

HYDRAULIC CONTROL VALVE Original Filed March 18, '1939 2 Sheets-Sheet ll/v l/EN TOES 1 ROBERT KJEFF'EEY,

AND

5TERU G C. MOON,

' HTT'Y.

Jan. 12,1943.

use, l5

R; JEFFREY a-rm. 2,308,285

HYDRAULIC CONTROL VALVE Original Filed March 18, 19:59 Z SheetS-Sheet 2W//// IOS/ jj'sleuhlcs C. MooN,

//v vsN o/es:

Patented Jan. 12, N43

HYDRAULIC CONTROL VALVE Robert K. defirey and Sterling C. Moon,Columbus, Ohio, assignors to The .l'efirey Manufacturing Company, acorporation of Ohio Original application March 18, 1939, Serial No.262,764. Divided and this application Decemher 5, 1940, Serial No.368,676

2 Claims.

This invention relates to an improved hydraulic control valveparticularly adapted for use in an improved hydraulic control system fora mining machine.

An object of the invention is to provide an improved power operatedhydraulic control valve.

Still another object of the invention is to provide a solenoid operatedhydraulic control valve which is adapted to control the rate of fluidflow therethrough in accordance with the current flowing in anelectrical circuit.

Another object of the invention is to provide a combined solenoid andmechanically operated hydraulic controlling valve adapted to varyprogressively the rate of flow of hydraulic liquid therethrough.

Other objects of the invention will appear hereinafter, the novelfeatures and combinations being set forth in the appended claims.

In the accompanying drawings,

Fig. 1 is an elevational view of the automatic volume control valve ofour invention showing its mounting on a mining machine frame shown insection;

Fig. 2 is a plan view of the valve of Fig. 1;

Fig. 3 is a sectional view taken on the line 3-3 of Fig. 1 looking inthe direction of the arrows;

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 1 looking inthe direction of the arrows;

Fig. 5 is a sectional view taken on the line 5--5' of Fig. 1 looking inthe direction of the arrows;

Fig. 6 is an enlarged sectional elevational view taken on the line 6-6of Fig. 2 looking in the direction of the arrows;

Fig. 7 is a sectional view taken onthe line l-=-'l of Fig. 6 looking inthe direction of the arrows, and also showing the manual operatingmechanism partly in section; and

Fig. 8 is an enlarged detail view taken on the line 88 of Fig. 6 lookingin the direction of the arrows..

This application is a division of our application Serial No. 262,764,filed March 18, 1939, for an improvement in 9. Mining machine.

As is pointed out in our parent application above identified, it isdesirable to regulate automatically the feeding movement of the kerfcutting mechanism, and this is preferably done in inverse proportion tothe ampere load ,on the driving motor. It is also preferred that thisinverse proportion be limited to less than the entire range of amperevariation. In practice, the mechanism is preferably adjusted so that thecutter mechanism is driven at full speed until the current reachesapproximately of its full 55 M8, sealed together load rating, whereuponthe feed rate of the kerf cutting mechanism is progressively decreasedas the current of the driving motor increases until it is finally shutoff at approximately 115% of its full rated value. It is, of course, tobe understood that the above is merely illustrative of the preferredrange and the range may be extended in either direction to any extentdesired.

It is,'of course, evident that with this automatic system the kerfcutting mechanism is operated at the maximum rate possible withoutundesirable overloading of its driving motor so that when easy cuttingis encountered, the feed rate is increased and when hard cutting isencountered the feed rate is reduced. Furthermore, when the drivingmotor for the cutting mechanism is not operated at all, or is merelyruning light as when no cutting operation is being performed, the feedrate for adjusting the various hydraulic piston motors is at a maximumthus providing for a high rate of adjustment to position the cuttermechanism for kerf cutting.

Th apparatus which provides for this automatic control as above setforth, is disclosed in detail in the drawings, which will now bedescribed.

As a general description, it may be stated that the automatic controlvalve, designated generally by the number 90, is operative to controlthe volume of fluid delivered to the operating hydraulic motors of thehydraulic system in accordance with the current flowing in an electricmotor such as that for driving the cutter chain of a mining machine asdisclosed in our parent application.

It is to be seen that the automatic control valve comprises a maincasting or body I of nonmagnetic material which has an integraldownwardly extending cylindrical portion I06 formed with-spaced integralflanges I01, I08 upon which cylindrical portion I06 and between whichflanges I01 and I08 is mounted an operating solenoid I09 containedwithin an insulating casing H0.

Removably attached to the top of the casting I05 is a valve casting orbody I l I of non-magnetic material which has a bottom integral flangeI41 by which it is attached to casting I05 by screws by seal wires I49and which is provided with a central longitudinally extendingcylindrical bore IIZ. Substantially midway of the casting H l is achamber, orifice or passageway H3 which isformed by the bore H2extending through a centrally disposed web H4. Above the web I I4 therei a circumferential port H5 communicating with the chamber H3 andprovided with a threaded opening H6 to which is threadedlpressure pipeor conduit 88.

It is thus manifest that port I I is the inlet or pressure port fordelivering fluid under pressure to the chamber, orifice or passageway H3which, it may be stated, is adjusted as to effective size so that thepressure drop across the same regulates a by-pass control valve, asdescribed in our parent application, to control the volume of fluid flowdelivered to the pressure pipe 88 and 92 and thence to the hydraulicpiston motors of the hydraulic control system. The structure of thisport H5 and the connection to it is illustrated in detail in Fig. 4 ofthe drawings. Directly below the web II4 there is a circumferential portIII communicating with the chamber H3 and provided with a threadedopening to which is threaded pressure pipe or conduit 92. It is thusmanifest that the port H1 is the outlet or receiving port for receivingfluid under pressure from the chamber, orifice or passageway I I3.

To provide an adjustment of the effective size of the chamber, orificeor passageway II3 there extends into the bore H2, a slidable piston H8of non-magnetic metal, the upper part of which is preferably, but notnecessarily, uniformly tapered at H9 and the extreme upper portion I ofwhich is generally cylindrical and is provided with oil seal grooves I2Ito reduce the liquid flow past said upper portion I 20. The centralportion of the piston H8 is formed as a shank I22 of reduced diameterwhich is normally positioned centrally of the chamber H3 therebyproviding a maximum efiective opening of said chamber H3 when the valve90 is in its normal position of adiustment.

Directly below the shank I22 is a generally cylindrical portion I23 ofthe piston H8 which is provided with oil seal grooves I24 to restrictthe flow of oil through the lower portion of the bore H2 designatedII2'. Extending downwardly from the cylindrical portion I23 is a shankI25 which, at its bottom, is pivotally attached to a plunger I26 ofmagnetic material by a loose connecting pivot pin I21, which plungerextends downwardly into a central opening I28 in the casting I05 withinwhich opening I28 is a helical spring I29, the upper end of which abutsan inattracts the plunger I 26 to pull it downwardly against the actionof the spring I29 which, after a predetermined movement, progressivelyreduces,

the effective size of the chamber, orifice or passageway H3 by theprogressive movement of the tapered portion H9 of piston I I8therethrough.

It is further manifest, that the effective size of said opening orpassageway H3 is inversely pro portional to the amount of currentflowing in the solenoid I09 once the tapered portion H9 of piston II8has entered said orifice or passageway H3. As previously suggested, inpractice it is preferred that a current of substantially 85% of therated current for the motor will be required before any appreciablereduction of the effective size of chamber, orifice or passageway H3 iseffected, and'that said passageway will be completely closed when thecurrent reaches approximately 115% of the rated value; the completeclosing, of course, being effected whenever the upper portion I 20 ofsaid piston I I8 enters the orifice or passageway H3, for itsubstantially completely fills it.

To provide for the manual adjustment of the automatic control valve sothat an operator may vary the action theerof, to reduce the feed ratebut, preferably, not to increase the feed rate, without regard to itstendency to operate automatically, said valve mechanism is provided withmanually operable mechanism including an operating handle I32 which ispivotally attached to a stub shaft I33 supported upon the valve castingIII by a Journal bearing I34 and journal bearing I35, the latter ofwhich is formed in a removable cap I36 which is attached to said castingIII by screws I31. A packing I38 is provided to prevent loss ofhydraulic fluid from. the valve about the shaft I33. Keyed to said shaftI33 is an operating shipper I39 which cooperates with a groove I40 in athrust collar I which bears against the top of the plunger I28. It ismanifest that by moving the handle I32 upwardly the control piston H8may be positively moved in a downward direction to reduce the feed rateas hereinafter pointed out. If desired, collar I may be rigidly attachedto shank I25 in which case the feed rate may be either increased orreduced manually and this may be either with or without the automaticcontrol provided by solenoid I09.

It may be stated that the forces acting on the piston H8 by virtue ofthe spring I29 and the solenoid I09 are relatively small as comparedwith the strength of an operator and may be at the maximum of the orderof fifteen pounds. Consequently, an operator will have no difficulty inadjusting the piston I I8 manually by the handle I32 without regard tothe tendency of the automatic mechanism to adjust said piston II 8.

As disclosed in our parent application, the automatic control valve 90is mounted adjacent the forward lefthand portion of the mining machineplatform and is carried on a horizontal plate I42 by virtue of a flangeI43 formed as an integral part of the casting I05, which flange isattached to the plate I42 as by screws I44. The handle I32 extendsforwardly through a slot in an upright plate I45 of said platform sothat said handle I32 is readily operable by the operator.

As seen by reference to Fig. 6 of the drawings, the central portion ofthe automatic control valve 90 provides a chamber I46 which will befilled with hydraulic fluid at all times due prim cipally to seepage,which hydraulic fluid will act as a lubricant for the moving partstherein and in the opening I28.

In the top of the casting III there is formed a chamber I50 whichcommunicates with the chamber I40 by way of passageway I5I.' Excesshydraulicfluid'is drained from the top of the chamber I50 by a returnpipe 83 (see Fig. 5).

To dampen somewhat the action of the piston .I I8 we provide inassociation with the upper portion I20 thereof a dash-pot, the structureof which is-best seen by reference to Figs. 6 and 8 of the drawings.Said dash-pot is formed by a cylindrical bore I52 in the top of saidupper portion I20 into which projects a piston I53 which is slightlyless in diameter than the diameter of the bore I52, said piston I53being formed as an integral portion of a plug I54 having enlargedportion I55 which is adapted to extend into and close the bore I I2formed in the extreme top portion of the casting III. The plug I54-additional- 157 has a top cylindrical portion I56 which is rigidlyattached to a removable top plate I51, for example as by having a pressfit therewith, which plate I5! is removably attached to the casting I lI as by screws I58.

To provide a control pressure conduit leading from the valve 90 toa highpressure relief valve which is responsive to the pressure in thepressure pipe or conduit 92 which, of course, is the same as thepressure in the port Ill, I provide a conduit which is formed by avertical bore I59 seen by reference to Fig. 5 of the drawings, the

bottom of which communicates with said port I ii. The vertical bore I59communicates with a transverse bore ISO to which is connected a pipe orconduit IIiI which leads to the pressure relief valve. As illustrated inFig. 5 01' the drawings, the top of the vertical bore I59, whichcommunicates with chamber I50, is closed by a threaded plug I62.

As was above set forth, there is a predetermined position for the pistonN8 of said control valve 90 for each current value between 85 percentand 115 percent of the rated load of motor connected in series withwinding IDS. This, of course, means'that orifice H3 has a predeterminedeflective size for every current value between the mentioned limits. Thepressure drop across orifice H3 is proportional to its effective sizeand the volume of hydraulic fluid flowing through it and entirelyindependent of the pressure of the hydraulic fluid. This drop inpressure across orifice 3 may be employed to control the by-passing ofhydraulic fluid as disclosed in our parent application, or otherwiseemployed.

Obviously those skilled in the art may make scope of the invention asdefined by the claims hereto appended, and we therefore wish not to berestricted to the precise construction herein disclosed.

Having thus described and shown an embodi-' ment of our invention, whatwe desire to secure by Letters Patent of the United States is:

1. A control valve comprising a body having a pressure chamber throughwhich hydraulic fluid is adapted to flow, movable valve mechanism insaid body for controlling the effective size of said chamber, anadditional chamber in said body separated from said first chamber bysaid valve mechanism and positioned below it and adapted to receive thehydraulic fluid which'leaks from said pressure chamber past said valvemechanism, electrical power operated means within said second chamberfor operating said movable valve mechanism, said means being lubricatedby various changes in the details and arrangement of parts withoutdeparting from the spirit and the hydraulic fluid which leaks into saidadditional chamber, and manually operable means for operating said valvemechanism including mechanismwithin said additional chamber lubricatedby said leaking hydraulic fluid.

2. A control valve comprisinga body having a pressure chamber-throughwhich hydraulic fluid is adapted to flow, movable valve mechanism insaid body for controlling the effective size of said chamber, anadditional chamber in said body separated from said first chamber bysaid valve mechanism and positioned below it and adapted to receive thehydraulic fluid which leaks from said pressure chamber past said valvemechanism, and electrically operated means within said secondchamber'tor operating said movable valve ROBERT K. JEFFREY. smanme c.MOON.

